A magnitude-5.6 earthquake rocked eastern Japan late on Monday, but no tsunami warning was issued, the Japan Meteorological Agency said.
There were no immediate reports of casualties or damage to property after the earthquake shook buildings in the capital Tokyo and surrounding areas.
The seismic centre of the quake that shook the region at 9:23 pm (1223 GMT) was in Ibaraki prefecture, east of Tokyo, the agency said. The quake struck at a depth of 40 kilometres.
Japan Atomic Power Company said there were no abnormalities at its Tokai No 2 Power Station, 100 kilometres north-east of Tokyo, broadcaster NHK reported.
Just a month ago, two major quakes struck Kumamoto prefecture on the southern island of Kyushu, leaving 49 dead and one missing.
The twin quakes in April were the strongest since the earthquake and resulting tsunami in the north-east in March 2011, which killed about 18,500 people and caused the nation’s worst-ever nuclear accident at the Fukushima Daiichi Nuclear Power Station.
Earthquake-prone Japan sits at the convergence of four tectonic plates.